Engine cowling



R. CHILTON ENGINE COWLING Nov. 7, 1933.

Filed March 2, 1931 INVENTOR. 12 UL AND CHILTON ATTOR Patented Nov. 7, 1933 UNITED STATES ENGINE COWLING Roland Chilton, Ridgewood, N. J., assignor to Wright Aeronautical Corporation, a corporation of New York Application March 2, 1931. Serial No. 519,655

7 Claims.

My invention relates to engine cowlings and especially to cowlings for radial air cooled aircraft engines,

Engines of this character often have the overall diameter thereof surrounded by a circular cowl or ring which usually interferes with the accessibility of the engine, and particularly with the accessibility of the rocker boxes which are points frequently requiring inspection and attention in this type of engine. Cowlings of this type are subject to heavy aerodynamic loads and severe mechanical vibration. Consequently difficulties frequently arise due to lack of stiffness and security of the fastenings and supports.

One object of this invention is to provide a cowling of the desired aerodynamic qualities which at the same time embodies an improved and simplified method for rigidly and securely supporting the cowling. A further object is to provide a construction that affords ready accessibility to the valves and rocker mechanism without removal of the cowling. A-further object is to provide a cowling which may be readily removed in sections but which shall be rigid when fastened in position in spite of the sectional construction. Other objects will appear later. I

In the embodiment of the invention illustrated the cowling is preferably divided into as many sections as there are cylinders, with a lapped but externally smooth joint between each of the cylinders. The outer diameter of the cowling conforms to the diameter of the engine over the rocker box covers, holes being formed in the cowling conforming to the profile of these covers.

At each of the rocker box covers, the cowling is provided with a sunken pocket which also forms a securing bracket. The base portion of this bracket or pocket is clamped between the rocker box cover and the rocker box. The base portion is cut away to the inner profile of the rocker box to afford access to the mechanism 45 therein when the cover is removed even though the cowling is in place.

Referring now to the drawing in which similar parts are designated by similar numbers:

Fig. 1 is a front view of 'a five cylinder radial air cooled engine having my improved cowling, the front edge of the cowling being broken away at one cylinder;

Fig. 2 is a side elevation of the same;

Fig. 3 is a fragmentary longitudinal section of the cowling taken radially through one of the rocker box bases with the rocker box cover removed; and

\ Fig. 4 is a fragmentary transverse section through one of the rocker-boxes showing the special form of rocker box cover used with this 80 cowling. I

In Figs. 1 and 2, 10 is the crankcase of the engine, 11 is one of the cylinders,- 12 and 13 are the rocker boxes with their covers, 14, 14; and 15, 15, are the sections of the cowling. 16 is es the lapped or locked joint between sections. The front edge when made as shown at 21, Fig. 3 is preferably simply rolled back and riveted.

The cowling in addition to the fastenings at the rocker boxes and the lapped or locked joints may be further secured by' a contractible band 22 with contracting screw 23, which may be placed either upon the surface of the cowling as shown, or in a groove so as to present a smooth exterior flush with the outer surface.

In Figs. 3-4, 12 is the engine rocker box, 14 the cover, 1'7 and 18 are the side and base respectively of the rocker box pocket, 18 being the part that is clamped to the upper surface 20 of the rocker box by the cover 14 by means of the screws, 19, 19. As stated above the base 18 is cut away to the inner profile of the rocker box to afford access to the mechanism therein when the rocker box cover is removed.

In Figs. 2 and 3, 24, 24 are the holes in the cowling for the rocker box covers.

The pockets, 1'7-18 may be separately stamped pieces, riveted to the sections, or may be formed integral with the sections 15. It is thus seen that this invention provides a cowling having the desired aerodynamic qualities, is firmly secured to the engine and provides accessibility to the engine parts for inspection, adjustment or repair.

While the cowling shown is practically cylindrical in general contour it is evident that the outer surface may be of such form as may be necessary to co-act, for the purpose of streamlining or otherwise, with adjacent parts of the fuselage or power plant.

While I have described my invention in detail in its present preferred embodiment, it willbe obvious to those skilled in the art after understanding my invention, that various changes and modifications: may be made therein without departing from the spirit or scopethereof. I aim in the v appended claims to cover all such modifications and changes.

What I claim is:

1. For use in combination with an internal combustion engine having a valve operating mechashaped and positioned that it cooperates with said cowling to form a substantially smooth streamlined surface.

2. For use in combination" with an internal combustion engine having a rocker arm, a rocker box for housing said rocker arm, a cowling sur rounding the outer diameter of said engine and having an openingadjacent to said rocker box,

and a rocker box cover so shaped and positioned that it cooperates with said cowling to form a substantially smooth streamlined surface.

8. For use in combination with an internal com-' bustion engine having a valve operating mechar nism positioned adjacent tothe outer diameter of 4. For use in combination with an internal combustion engine having rocker arms, a rocker box surrounding and housing each rocker arm, a cowling surrounding the outer diameter of said engine and having openings adjacent to each of ;said rocker boxes, anda rocker box cover for 0 adjacent to the outer diameter of said engine; a cowling surrounding the outer diameter of said engine and having openings adjacent to each said rocker box; extensions secured to said cowling, one each at each opening, each of said extensions being formed with a side portion and a base portion and the base portion being.formed with an opening through which access to the rocker arm may be obtained; a rocker box cover for each rocker box secured within the associated opening in the cowling and covering the associated opening in the extension, said cover having its outer surface. positioned 1 substantially flush with the outer surface of the cowling; and means for securing the associated rocker box cover and the associated cowling extension firmly to each rocker box comprising screws for each rocker box passing successively through the rocker box cover, the cowling extension and into the rocker box.

6. In combination with an internal combustion engine including a plurality of radially extending cylinders having housings for auxiliary engine mechanism at their outer ends, a'cowling sur-' rounding the outer cylinder ends having openings for access to, and conforming substantially in shape to, each said housing.

7. In combination with an internal combustion engine including a plurality of radially extending cylinders having housings for auxiliary engine mechanism at their outer ends, a cowling surrounding the outer cylinder ends having openings for access to, and conf orming substantially in and having their outer surfaces substantially flush with said cowling.

ROLAND crmxron 

